Digital media distribution device

ABSTRACT

A digital media distribution device that includes an encoder, a decoder coupled to the encoder, and a transcoder coupled to the decoder. The encoder is configured to encode input data that is received by the digital media distribution device into a first data format. The decoder is configured to decode output data to be output by the digital media distribution device. The transcoder is configured to convert the encoded input data from the first data format into a second data format. The digital media distribution device is configured to be coupled to a computer network.

CROSS-REFERENCE TO RELATED APPLICATION

Priority is claimed under 35 U.S.C. §119(e) to U.S. Provisional PatentApplication No. 60/494,396, filed on Aug. 11, 2003, entitled “DigitalMedia Distribution Device,” by Paul Klamer, Ken Long, and ArjunRamamurthy, which application is incorporated by reference herein.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates generally to the field of data manipulation andstorage. More specifically, the invention relates to devices thatmanipulate and store image, sound, and associated metadata.

2. Description of Related Art

In the entertainment industry, the video tape recorder (“VTR”) hasserved for many years as the main device for storing video andaccompanying audio. However, there is a need for an apparatus thatprovides capabilities beyond those offered by the VTR. In particular,there is a need for an apparatus that can store data onnetwork-accessible mass storage devices, e.g., disk drives.Additionally, there is a need for an apparatus that can transcode databetween different data formats. Accordingly, there is a need for anapparatus that can store data on network-accessible storage devices andtranscode data between formats. The present invention satisfies theseneeds.

SUMMARY OF THE INVENTION

Embodiments of the present invention include a digital mediadistribution device that includes an encoder, a decoder, and atranscoder, which transcodes between data formats. The digital mediadistribution device interfaces with a shared storage device for datastorage. An exemplary embodiment of the present invention is a digitalmedia distribution device that includes an encoder, a decoder coupled tothe encoder, and a transcoder coupled to the decoder. The encoder isconfigured to encode input data that is received by the digital mediadistribution device into a first data format. The decoder is configuredto decode output data to be output by the digital media distributiondevice. The transcoder is configured to convert the encoded input datafrom the first data format into a second data format. The digital mediadistribution device is configured to be coupled to a computer network.

In other, more detailed features of the invention, the encoder anddecoder are housed within a single electronics rack. The electronicsrack includes a hardware slot, and an interface board that is configuredto insert into the hardware slot. The interface board supports aninterface format selected from the group consisting of SD-SDI, HD-HDI,GSN, uncompressed AES-3, unbalanced BNC, and balanced XLR. Also, theencoder and decoder are remote controllable. In addition, a computerterminal unit is coupled to the encoder and the decoder.

In other, more detailed features of the invention, the encoder and thedecoder perform a verification check and report their status to a userbefore processing data. In addition, the encoder is configured tocalculate a peak signal-to-noise ratio value when the encoder and thedecoder are coupled in a closed-loop configuration. In addition, thetranscoder is implemented in software on a personal computer.Furthermore, the transcoder includes a PCI accelerator board having ASICaccelerators. Also, the transcoder converts between data formatsselected from the group consisting of JPEG2000, MPEG-2, minimally ATSC(high definition), DVD elemental bit stream, DVB (625), and 4:2:2.

In other, more detailed features of the invention, the digital mediadistribution device is configured for wavelet-based tunable compression.Also, the digital media distribution device has a form factor and a userinterface that approximate the form factor and the user interface for avideo tape recorder. In addition, the digital media distribution deviceincludes a codec and an operating system, and the codec and theoperating system can be upgraded by a user. Furthermore, the encoderencodes data at an encoding bit rate, the decoder decodes data at adecoding bit rate, and the encoding bit rate and the decoding bit rateare user definable.

In other, more detailed features of the invention, the digital mediadistribution device is an internet protocol addressable device. Also,the digital media distribution device is coupled to the computernetwork, and the digital media distribution device is coupled to anetwork-accessible storage device via the computer network. Furthermore,the encoder, the decoder, and the transcoder each include cache memoryused to compensate for latency associated with accessing thenetwork-accessible storage device. Also, the digital media distributiondevice is coupled to an asset management system, and the assetmanagement system can determine end of file location information andasset information for the data.

Other features of the invention should become apparent from thefollowing description of the preferred embodiments taken in conjunctionwith the accompanying drawing, which illustrates, by way of example, theprinciples of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of a digital media distribution deviceaccording to a preferred embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to FIG. 1, embodiments of the present invention are includedin a digital media distribution device (“DMD device”) 10 that compressesinput data for storage and decompresses stored data to be output fromthe DMD device. The DMD device includes an encoder 12, which compressesthe input data received from an external device (not shown), e.g., filmscanner; a decoder 14, which decompresses the data for output whilepreserving color matrices and properly adjusting the image size; and atranscoder 16, which converts the data between various data formats.

The encoder 12 and decoder 14 are rack-mountable and can be housedwithin a single electronics rack (not shown), or in two separateelectronics racks (not shown) for playback-only or record-onlyconfigurations, and can be remotely controlled using various remotecontrol formats, e.g., Sony RS-422 VTR control. The encoder, decoder,and transcoder 16 are coupled, via interface lines 18, 20, and 22,respectively, e.g., fiber or copper Ethernet interfaces, to a computernetwork 24, e.g., Ethernet. Accordingly, the encoder is coupled to thedecoder via the computer network. Also, a computer terminal unit 26 iscoupled to both the encoder and the decoder via RS-232 lines 28 thatcouple to RS-232 ports (not shown) on the encoder and decoder. Thecomputer terminal unit allows an operator to control the decoder and theencoder. Also, the computer terminal unit can be network assignable soit can be physically separated from the encoder and the decoder.

A server 30, e.g., a New Technology (“NT”) server or a Unix box, iscoupled to the computer network 24 via a server interface line 32, and anetwork accessible data storage device 34 is coupled to the server via astorage device interface line 36. The data storage device can be any ofthe standard storage devices known in the art. While FIG. 1 depicts oneserver and network storage device, more than one server and more thanone network storage device can be coupled to the computer network andaccessed by the DMD device 10.

The DMD device 10 is a network addressable device, e.g., an internetprotocol (“IP”) addressable device, thus the DMD device permits remoteaccess via the computer network 24 for configuration, operation,diagnostics, and upgrades. The DMD device is designed to utilizedatabase standards, e.g. SQL, and thus can interface with a standarddatabase server 30. The operating system (“OS”) for the DMD device canbe any open and customizable OS, e.g., Linux.

Both the encoder 12 and the decoder 14 each include a front-end module(not shown), a mid-region module (not shown), and a back-end module (notshown). Encoder's front-end module interfaces with the computer network24 and receives input signals from the computer network. The encoder'sfront-end module includes slots (not shown) into which various interfacecards can be inserted to handle different input formats, e.g., highdefinition (“HD”), standard definition (“SD”), and gigabyte systemnetwork (“GSN”). The encoder transfers the data received by theencoder's front-end module to the encoder's mid-region module where thedata is compressed. After the data is compressed, the encoder transfersthe compressed data to the encoder's back-end module, which transfersthe compressed data via the computer network and the server 30 to thenetwork storage device 34.

The decoder's back-end module (not shown) interfaces with the computernetwork 24 and receives data from the network storage device 34 via theserver 30. Next, the decoder 12 transfers the compressed data from theback-end module to the mid-region module where the compressed data isdecompressed. Finally, the decoder transfers the decompressed data fromthe mid-region module to the decoder's front-end module which outputsthe data, e.g., SD or HD video data, to the user based on theuser-defined configuration.

Both the encoder 12 and the decoder 14 are of a modular building blockconfiguration, which allows for the expansion of encoder and decodercapability. As mentioned previously, the encoder and the decoder arerack-mountable, each with a maximum foot print of two rack units(“RUs”). The rack space for the combination of all of the encodermodules (not shown) and the decoder modules (not shown) can extend, forexample, to a total of six RUs.

Both the encoder's front end module (not shown) and the decoder'sfront-end module (not shown) include reconfigurable hardware slots intowhich various interface boards, e.g., Ethernet board including eitherfiber or copper interfaces, can be installed to handle various inputtypes (encoder) and output types (decoder). Since the interface type forboth the encoder's front-end module and decoder's front end module canbe reconfigured, the encoder and decoder can be customized to match thedesired interface type. In particular, the interface type for both theencoder's front-end module and the decoder's front-end module can bereconfigured to support an SD (e.g., NTSC standard=525 lines or PALstandard=625 lines) serial data input (“SD-SDI”) stream, an HD (e.g.,1920 by 1080 interlaced pixels) serial data input (“HD-SDI”) stream, oran optical GSN stream.

In one example, the encoder's front-end module (not shown) and/or thedecoder's front-end module (not shown) can be configured to include dual292 HD-SDI interfaces, five audio channels interfaces, and a time codeinterface. Embodiments that include dual HD-SDI advantageously providefull color, i.e., red, green, blue data (“RGB”) at 4:4:4, rather thansub-sampled color, i.e., RGB at 4:2:2, which is provided when theinterfaces are single HD-SDI interfaces. In another example, theencoder's front-end module or the decoder's front-end module includes 48audio channels interfaces. In yet another example, both the encoder'sfront-end module and the decoder's front-end module are configured withSD-SDI, HD-SDI SMPTE 292, and 8 audio channel interfaces such that boththe encoder and the decoder have a combined front-end module bandwidthof 3.5 gigabits per second and a combined back-end module bandwidth ofat least 1 gigabit per second.

Furthermore, the slots (not shown) in the encoder's front-end module(not shown) and the decoder's front-end module (not shown) can beconfigured to include interfaces for encoding/decoding audio data, whichcan be in various audio formats, e.g., uncompressed AES-3, unbalancedBNC, and balanced XLR. Both the encoder 12 and the decoder 14 can alsohandle embedded audio in 292 or 601 bit stream configurations. Theimplemented audio file format should be lossless with a mechanism tosync with the corresponding video format for transcoding and decoding.An example audio format supports a 96 kHz sample rate and a 32-bitdepth.

Both the encoder 12 and the decoder 14 include a time code that supportsthe linear time code (“LTC”) and vertical interlaced time code (“VITC”)standards, including drop frame/non-drop frame. For the decoder, both ananalog timecode and a digital timecode are available over an RS-422serial port. Also, the decoder supports error concealment, for on-airuse, and provides for disabling error concealment, for mastering. Theuser has the ability to turn the concealment on and off. Also, thedecoder supports standard VTR functionality, for example, jog dialplayback, pause, and rewind. In addition, the decoder supports theability to adjust the size, aspect ratio, and resolution of an image.

Before the encoder 12 and the decoder 14 are used, the encoder and thedecoder perform a file system performance verification check and reporttheir statuses to the user. Also, the encoder and the decoder reporttheir ability to perform proper encoding and decoding based on thestatuses of their boot batteries and the results of bandwidth tests. Theboot battery is the internal battery source included in both the encoderand the decoder that is used to power memory devices, e.g., EEPROMs,that hold the boot information for the encoder or decoder. Also, boththe encoder and the decoder can perform video/audio diagnosticcapability checks such as tone and test pattern reading.

The encoder 12 and the decoder 14 can be coupled in a closed-loopconfiguration (not shown). In the closed-loop configuration, the encodercan calculate a value of peak signal-to-noise ratio (“PSNR”) accordingto the following equation:PSNR=20 log (RMS error),

-   -   where the RMS error is the square root of the squared value of        the encoder-decoder system's average error measured by the        encoder squared.

The PSNR value is output to the user on the computer terminal unit 26and can be monitored by the user or a remote device (not shown) and usedto determine if the quality of the encoding is sufficient, or if theencoding bit rate needs to be adjusted.

The transcoder 16 is housed within a personal computer 38 and can beimplemented as a software module that can run on more than one computer.Furthermore, the transcoder can incorporate a peripheral componentinterconnect (“PCI”) accelerator board (not shown) with ApplicationSpecific Integrated Circuit (“ASIC”) accelerators for improvedperformance. The transcoder utilizes a database, e.g., an SQL-compliantdatabase, for job actions, and processes transcoding jobs according to acustomizable priority structure. More specifically, the transcoderhandles job delegation, queuing, prioritization, delivery, and hand-off.The transcoder delivers transcoded output to the network storage device34 via the computer network 24.

User interaction with the transcoder 16 is implemented via a graphicaluser interface (“GUI”) and command line interface (“CLI”). Through theGUI, users can select a data file to transcode and submit the job forprocessing. The GUI is generic, able to run on multiple platforms, andis customizable to support the creation of interfaces for different jobfunctions. The transcoder also is able to accept transcoding commandsvia a command line interface (“CLI”) though a remote shell (“RSH”),which allows for remote login to the transcoder.

The transcoder 16 can transcode between various data formats, e.g.,JPEG2000, MPEG-2, minimally ATSC (high definition), DVD elemental bitstream, DVB (625), and 4:2:2, with full user configurability ontranscode options. Also, the transcoder allows the user to adjust thebit rates, frame rates, resolution, broadcast format, GOP structures,audio repackaging, and syncing schemes of the data. The transcoderprocesses intermediate RGB data and add burn-in elements. Also, thetranscoder converts different field orders (both lower and upper). Thetranscoder can output asset recreation instructions (“metadata”) so thatthe transcoded version of the data can be recreated if demanded. Thetranscoder can first store the transcoded output data to the networkstorage device 34, and then forward the transcoder's output to anotherdevice (not shown), e.g., additional disk storage.

All storage of data for the encoder 12, decoder 14, and transcoder 16,is accomplished using the network storage device 34, which is accessibleover the computer network 24 through the server 30. The encoder,decoder, and transcoder all include cache memory (not shown), which isused to compensate for latency associated with accessing the networkstorage device. The size of the cache memory in each of the encoder, thedecoder, and the transcoder is sufficient to prevent lag duringhigh-latency conditions. File systems, e.g., common internet file system(CIFS/SMB) or network file system interface—NFS-V3, are included in theDMD device 10 that support the storage of encoded files to the networkstorage device. The DMD device can also include a hierarchical storagemanagement (“HSM”) system (not shown) via standard HSM protocols, oreven Extensible Markup Language (“XML”) tags, which control the storageof the encoded data.

Furthermore, the DMD device 10 has the ability to communicate with anasset management system (not shown), which permits the user to track andmanage the data (“the asset”). The asset management system can be usedto determine the end file location information and asset identificationof the data. In one example, an asset management system could be used tolocate where a specific take of a scene in a film is stored in thenetwork data storage device 34.

Advantageously, the DMD device 10 according to the present invention, inaddition to functioning as a VTR, has a form factor and user interfacethat is similar to, approximate, that of a VTR. The DMD device canoperate either as a stand-alone device or a network-accessible device.When the DMD device is coupled to a computer network 24, the DMD devicecan benefit from backup servers (not shown) that provide data in theevent of a failure of the network data storage device 34. Also, the DMDdevice advantageously includes an output mechanism that indicates thestatus and configuration of the encoder 12 and the decoder 14. Forexample, the DMD device can measure the boot battery value and bandwidthof the encoder and decoder prior to use. When power is applied to theencoder and decoder, the encoder and decoder use their boot battery forinitialization purposes, and the encoder and decoder measure theavailable network bandwidth and characterize the computer networkthroughput and performance based on the current network bandwidth andusage. This information is output to the user via a monitoring device,e.g., the computer terminal unit 26.

Another advantage of the DMD device 10 is that the codec and OS areupgradeable in both the encoder 12 and decoder 14 since the OS is storedon Flash ROM (not shown) and the codec is implemented using a pin gridarray (“PGA”)-based architecture (not shown). The codec and the OS canbe upgraded in the server mode, where the DMD device checks for updatesfrom a server, via the computer network, and then proceeds to operation.Alternatively, the codec and the OS can be upgraded in the stand alonemode, where updates can be administered through the computer terminalunit 26. Furthermore, the computer terminal unit can communicate withthe encoder or decoder in case of boot failures, notifications, orstatus messages. The encoder or decoder can be instructed, via thecomputer terminal unit, through command line interface (“CLI”) scripts.Also, CLI scripts can be used to control the transcoder.

Advantageously, the DMD device 10 can support the encoding and decodingof data files at bit rates set in user-definable profiles (not shown).The profiles are stored on the server 30 and can be accessed by a remoteuser when changing the bit rate for a specific input job. The bit ratecan change from lossless to lossy, which could be from no degradation toabsolute degradation in image quality. Also, the bit rate can bedifferent between the bit rate input to the DMD device and the bit rateoutput from the DMD device, e.g., if the input bit rate is 10 bits perpixel, the output can vary from 10 bits per pixel (no loss) down to 0.1bit per pixel (lossy). Furthermore, the digital media distributiondevice provides for wavelet-based tunable compression, for example, withJPEG2000 data.

The foregoing detailed description of the present invention is providedfor purposes of illustration, and it is not intended to be exhaustive orto limit the invention to the particular embodiments disclosed. Theembodiments can provide different capabilities and benefits, dependingon the configuration used to implement the key features of theinvention. Accordingly, the scope of the invention is defined only bythe following claims.

What is claimed is:
 1. A digital media distribution (DMD) devicecomprising: an encoder that is configured to receive a video signalsolely from an external network, to encode the video signal to generatecompressed video data, and to output the compressed video data solely tothe external network, in response to control input from a computerterminal; a decoder, housed with the encoder in the DMD device andconfigured to receive the compressed video data solely from the externalnetwork, and to decode the compressed video to generate the video signalfor output from the DMD device, in response to control input from thecomputer terminal; wherein the external network and computer terminalare both external to and separate from the DMD device, and the encoderand the decoder are configured for direct communication with each othersolely via the external network and are not communicatively coupled toone another except by the external network; and a transcoder coupled toat least one of the encoder or decoder via the external network, thetranscoder configured to transcode the compressed video data from afirst data format to a second data format.
 2. The DMD device of claim 1,wherein the encoder and decoder are housed together in at least oneelectronics rack.
 3. The DMD device of claim 1, wherein the encoder isconfigured to receive input signals from the external network via areconfigurable hardware slot adapted to support an interface formatselected from the group consisting of SD-SDI, HD-HDI, GSN, uncompressedAES-3, unbalanced BNC, and balanced XLR.
 4. The DMD device of claim 1,wherein the encoder and the decoder are remotely controllable.
 5. TheDMD device of claim 1, wherein the encoder performs a file systemperformance verification check and reports its status before encodingdata.
 6. The DMD device of claim 1, wherein the encoder is configured tocalculate a peak signal-to-noise ratio value when the encoder and thedecoder are coupled in a closed-loop configuration.
 7. The DMD device ofclaim 1, wherein the encoder and decoder are configured forwavelet-based tunable compression.
 8. The DMD device of claim 1, furthercomprising an operating system and codec each capable of being upgradedby a user.
 9. The DMD device of claim 1, wherein encoding and decodingare performed at bit rates stored in user-definable profiles.
 10. TheDMD device of claim 1, wherein the encoder and decoder are internetprotocol addressable devices.
 11. The DMD device of claim 1, wherein thedecoder supports standard VTR functionality including at least jog dialplayback, pause, and rewind.
 12. The DMD device of claim 1, wherein thetranscoder comprises software operating on a personal computer.
 13. TheDMD device of claim 1, wherein the transcoder utilizes a databaseprioritizing transcoding jobs according to a customizable prioritystructure.
 14. The DMD device of claim 1, wherein the transcoderconverts between data formats selected from the group consisting ofJPEG2000, MPEG-2, minimally ATSC (high definition), DVD elemental bitstream, DVB (625), and 4:2:2.
 15. The DMD device of claim 1, furthercomprising a storage device coupled to the DMD device via the externalnetwork.
 16. The DMD device of claim 15, wherein the storage devicereceives the compressed video data from the encoder via the externalnetwork and stores the compressed video data.
 17. The DMD device ofclaim 16, wherein the decoder receives the compressed video data storedin the storage device from the storage device via the external network.18. The DMD device of claim 15, wherein the encoder, the decoder, andthe transcoder each include cache memory used to compensate for latencyassociated with communications with the storage device via the externalnetwork.
 19. The DMD device of claim 15, further comprising an assetmanagement system, wherein the asset management system can determine endof file location information and asset information for the compressedvideo data stored in the storage device.